This paper describes the experimental investigation of relationship between splitting tensile strength and flexural strength with the compressive strength of concrete containing waste PET as fine aggregates replacement. Waste PET was reprocesses and used as the artificial fine aggregate at the replacement volume of 25%, 50% and 75%, Cylindrical and prism specimens were tested to obtain the compressive, splitting tensile and flexural strength at the age of 28 days. Based on the investigation, a relationship for the prediction of splitting tensile and flexural strength was derived from the compressive strength of concrete containing waste PET as fine agglegate replacement.

This research is carried out to investigate the performance of concrete containing Polyethylene Terephthalate (PET) bottle waste as fiber. PET bottle waste was chosen because it is being thrown after single use and cause environmental problem. One way to recycle wasted PET bottles is grinded into irregular fiber. Then, it was incorporate with the concrete and test the performance of the concrete. The study was conducted using cylindrical mold of concrete to investigate the performance of the concrete in term of mechanical properties. A total of four batches of concrete were produced namely, normal concrete and concrete containing PET fiber of 0.5%, 1.0% and 1.5% fraction volume. In this research, the mechanical properties that were measured are compressive strength, splitting tensile strength and modulus of elasticity (MOE) following British Standard method. The results revealed that the presence of PET fiber in concrete will increase the concrete performance. Nevertheless, the content of PET fiber was specified in a specific limit to avoid effect of concrete strength.

The paper reviewed the current perspectives on the development of carbon dioxide (CO₂) sequestration through its process conversion into calcite. The process occurs in either geological or biological systems. However, geological sequestration is an expensive process, which is slow in comparison to bio-sequestration. Recently, the bio-sequestration of atmospheric CO₂ into the soil using microorganisms such as algae has been investigated. However, the algae cannot be used in the bio-concrete due to their nature as phototrophic organisms. In contrast, bacteria are the most potent organisms in bio-concrete technology. The use of bacterial species in the bio-aerated concrete bricks (B-ACB) and its potential to bio-sequestrate CO₂ represents a future strategy to reduce high CO₂ pollution. Bacterial cells can capture CO₂ by accelerating the carbonation processes, which convert CO₂ into calcium carbonate (CaCO₃) via carbon anhydrase and urease enzymes. The present paper aimed to highlight and discuss the applicability of bacteria in the B-ACB for capturing and storing CO₂. It is evident from the literature that the new trends to use bio-concrete might contribute to the reduction of CO₂ by accelerating the carbonation process and strengthening the B-ACB.